Drew Roy provides one of the creepier moments in Season 3 of "Falling Skies," which just four episodes in has delivered a number of creepy occurrences. (Stop reading if you're not caught up! Spoilers ahead!)

In the June 23 episode, "At All Costs," Roy freaked out fans when his character, Hal Mason—well, I'll let Roy explain the "fun" scene:

"[Hal] doesn't trust himself [and decides,] ‘You've got to leave town,'" Roy said during a phone conversation. Hal finally realized that he had been compromised by the alien earbug and that he was under the influence of the Espheni aliens that are trying to conquer humankind.

"He goes into his room to sort of think things out and he's all worked up. And the next thing he knows somebody's talking to him in the mirror—which is never good."

The ensuing argument ends with Hal smashing the mirror, which only served to let Evil Hal and his sinister smile loose for good. After that mirror cracked, Evil Hal gave the Espheni intel on what's happening in Charleston and about his dad Tom's (Noah Wyle) meeting with the president (Stephen Collins). He also helped the Espheni kidnap Anne Glass (Moon Bloodgood) and her baby, Alexis (his half sister).

"That's how I like to play Evil Hal—as this very cunning, manipulative guy who was just as confident as he needed to be," Roy said, explaining that after Evil Hal took over, he had to find Maggie and show her that the months of doubt Good Hal had been feeling was long gone. "He gets her to forget all about it [with] one simple little walk and talk. And then he lays a kiss on her. Cut to them in the bed—a wild passionate moment—and that's how good Evil Hal is. He knows how to push her buttons.

"He knows how to push most of the top people in Charleston. So he's quite a dangerous threat to everyone that lives in that town."

Roy had fun playing an evil character this season, he said, but he was constantly checking himself to make sure Hal didn't become a caricature of evil. He wanted to make sure he always had a good reason for playing a moment with malice and not just to "twist my mustache."

"Between the writers writing me such fantastic stuff to play and then putting the work in and reading it with friends ... and the guidance of somebody like Noah Wyle on set really helps a lot," he said. Wyle not only offered advice when Roy sought it out, but he always had an encouraging word.

"That just instills such a confidence in you, which is a huge thing for an actor," he said. "When you start doubting yourself it gets really hard to stand up in front of a hundred people who are all working on a show knowing that millions of people watch the show and to have that confidence. So I feel like I'm surrounded by a very, very generous cast."

And just in case you think that smirk will leave Evil Hal's face any time soon, well, Roy said the mirror scene was just the beginning of "the good stuff."

"In the fifth episode we're going to watch him sort of stake out his prey and slowly put everyone at ease who had a suspicious look toward him," Roy teased. "But it all is going to culminate in the sixth episode. That is my favorite episode that I've ever shot. It doesn't have a whole lot of flash and bang, but you are on the edge of your seat the entire time.

"We're going to see the most evil Hal that we've seen ever."

The fifth episode, "Search and Recover," airs at 9 p.m. CT Sunday, June 30. The sixth episode, "Be Silent and Come Out," airs at the same time July 7, both on TNT.Want more? Discuss this article and others on Show Patrol's Facebook page.